How precise is your powder measure?

[ATAShooter]

My Measures ???

Well, if I am loading Bang-bang shoot-em-up ammo, I do a volume measure ( Lee disc or Perfect powder measure ). If I am going presision rifle, then a beam scale and a trickler.

 

[meanmotorscooter]

Using the Lee pro auto disk measure with single disk and double disk kit I have never been off more than .1 on the ones that were measured. We will always wonder about the ones we don't measure. From what I hear extruded powders are harder to measure in most powder measures. I have sat down for three hours many times to load 9mm with 4.2 grains of Titegroup and every round I check the powder drop on weighs exactly 4.2 grains. I would try some different powder and see if you have better results.
Rusty

Could you please explain how you achieved 4.2 grains of Titegroup. I don't have the double disk setup but for me the .37 hole throws 3.9 grains and the .40 hole throws 4.4. I would like to get 4.2-4.3. I have tried the adjustable charge bar and about every 4 pull I get no powder in the case. Does anyone else have this problem with the adjustable charge bar? Can someone explain to me how to get 4.2-4.3 grains of Titegroup with the Lee Pro Auto Disk?

 

[JJE]

1. What measure are you using? RCBS Uniflow
2. What type of powder? W231, 2400, Reloder 7 (all "good-metering" powders)
3. Weight of your typical powder charge? W231: 3-5 gr 2400: 9-15 gr Re7: 29-31.5 gr
4. Are you consistently getting throws +/- 0.1 gr or better? Probably not. For handgun, I've decided there's no point trying to work up loads in 0.1 gr intervals because when it comes time to make them in "bulk" (using a single-stage press but without weighing each charge) they are going to vary as much as 0.1, so a 3.0 gr load might actually be 2.9 or 3.1 grains. Most of my handgun loads are light target loads so it doesn't really matter, since my shooting errors mask any accuracy errors resulting from a 0.1 gr difference in charges, and I'm not using max loads where an extra 0.1 gr is going to over-pressure the gun. For rifle and hunting handgun, my loads are max or close to max, so I weigh each charge (throw a light load on the Uniflow, then bring it up to spec with a trickler).

5. If worse than that, +/- how much? For handgun, I weight every 10 rounds or so, just because I'm paranoid, and they probably never vary more than about 0.1 gr with the powders I use.

 

[Bart B.]

Considering that Sierra Bullets uses metered powder charges (about 3/10ths spread) to test fire their 30 caliber bullets and their best MatchKings get 10-shot groups in the ones (under .2 MOA); precise charge weight ain't all that important.

I'm convinced stool shooters (those good folks also called bench resters) could almost use a tea spoon to measure powder charges and still shoot one holers up through 200 yards. It's often too windy at their shoots to weigh charges and besides it takes too much time.

Check your ballistic tables for down range bullet drop at different muzzle velocities. When I first did this, I was a bit awed by the fact that at 100 yards with a .308 Win., a 50 fps spread in muzzle velocity typically would cause only 1/10th inch vertical shot stringing. 'Course at 1000 yards, it would be about 20 inches. Which means 1/10th MOA at short range and 2 whole MOA's at a very long range.

I helped develop loads for Sierra's 30 caliber 155-gr. Palma bullet back in 1991. We settled on IMR4895 and the loading crew put out some 200 thousand rounds in new Winchester cases primed with Federal 210M's. Charge weight spread was about 3/10ths of a grain from the powder measure atop the Dillon 1050 progressive used for charging and bullet seating. Random accuracy tests at 600 yards had 20 shot group about 3 inches. Same accuracy was in many other rifles from around the world when that bullet was used for the first time in competition. That ammo would probably shoot 1/4th inch or better at 100 yards.